Friction materials such as disc brake pads and brake linings are used for the purpose of braking in automobiles and the like. The friction material fulfills the role of braking by friction with a facing material such as a disc rotor, a brake drum or the like. Therefore, it is required for the friction material to have a stability of the friction coefficient (fade resistance) and a high friction coefficient in the braking temperature range which is wide from low temperature to high temperature. In addition, pedal feeling characteristics during braking (shortening of time to stabilization from the start of braking) is required.
Such a friction material contains components such as a binder, a fibrous base material, an inorganic filler and an organic filler, and one kind or two kinds or more in combination are used, in general, for each component in order to develop the above-mentioned characteristics. As the fibrous base material, organic fibers, metal fibers, inorganic fibers and the like are used, and copper fibers and copper alloy fibers are used as the metal fiber for improving wear resistance. Also, so-called non-asbestos friction materials, which do not contain asbestos, are main stream as friction materials. However, for this non-asbestos friction material, a large amount of copper or copper alloy or the like is used (Patent Literature 1, etc.).